Self-moving sweeping device

ABSTRACT

A self-moving sweeping device comprises a device body and at least two movement wheels and a direction change wheel located at the bottom of the device body. The direction change wheel includes a magnetic element which is turnable therewith and has a first magnetic pole and a second magnetic pole that are repulsive against each other in magnetism. The device body includes a magnetic induction unit faced the direction change wheel. During movement of the device body the magnetic induction unit detects in normal conditions whether the first magnetic pole has generated a detection signal sent to a behavior control module which determines whether the self-moving sweeping device moves abnormally based on whether the detection signal has been continuously received within a monitor time; if positive, judges the self-moving sweeping device moves normally; otherwise, abnormally.

FIELD OF THE INVENTION

The present invention relates to a self-moving sweeping device and particularly to a self-moving sweeping device enabled to judge abnormal movement based on a direction change wheel movement status.

BACKGROUND OF THE INVENTION

With advance of technology nowadays many types of cleaning devices also are built with automation and intelligence capability. Many families in general prefer to purchase multi-functional cleaning devices. Among them dust suction device is the most commonly used household cleaning device. However, the conventional dust suction device generally is bulky in size and difficult for storing. Moreover, it usually generates very high decibel noise during dust suction operation that hinders its acceptance. To resolve these problems self-moving sweeping devices have been developed and marketed. They can move in various types of locus during dust suction operation to overcome environmental obstacles in the sweeping area.

However, in the event that a self-moving sweeping device encounters a bump or indented obstacle it does not make proper response and still maintains forward movement continuously. This could cause the direction change wheel suspending, and the self-moving sweeping device could be trapped by the obstacle and unable to continue sweeping task on other areas. To resolve such an issue, a self-moving sweeping device equipped with an escape mechanism has been developed. For instance, Taiwan utility patent No. M377197 discloses a technique which has a direction change wheel with a side wall to block intermittently a sensing light projecting to the direction change wheel during rotation and a signal receiving element to receive intermittently the sensing light to determine whether the direction change wheel functions normally. However, it requires a signal sending element to send the sensing light that has to be positioned precisely against the signal receiving element. Such a positioning process cannot be done quickly that makes production more difficult. Moreover, during turning of the direction change wheel trashes such as hairs tend to be entangled thereon that could hinder the light path of the sensing light and make the signal receiving element unable to receive the sensing light, and faulty judgment could take place.

SUMMARY OF THE INVENTION

The primary object of the present invention is to solve the problems of the conventional self-moving sweeping device of difficulty in assembly and easily interfered by external objects that results in abnormal induction.

To achieve the foregoing object the present invention provides a self-moving sweeping device that comprises a device body, at least two movement wheels and a direction change wheel. The device body is equipped with a dust suction module, a drive module and a behavior control module connected to the dust suction module and the drive module. The behavior control module determines work of the dust suction module and the drive module. The movement wheels are located at the bottom of the device body and connected to the drive module, and driven by the drive module to generate rotation to drive the device body to move. The direction change wheel also is located at the bottom of the device body with the movement wheels and controlled by the drive module to guide direction turning of the device body. The direction change wheel has a magnetic element which is turnable with the direction change wheel and includes a first magnetic pole and a second magnetic pole that are repulsive against each other in magnetism. The device body has a magnetic induction unit faced the direction change wheel. During movement of the device body the magnetic induction unit detects in normal conditions whether the first magnetic pole has generated a detection signal sent to the behavior control module which based on whether having continuously received the detection signal within a monitor time determines whether the self-moving sweeping device is moving abnormally. In the event that the detection signal has been continuously received within the monitor time movement of the self-moving sweeping device is judged normal; otherwise is abnormal.

In one embodiment the behavior control module captures the appearing frequency of the detection signal within the monitor time and converts to a frequency signal based on which to judge whether the self-moving sweeping device is moving abnormally. In the event that the frequency signal changes and decreases gradually the self-moving sweeping device is judged abnormal in movement.

In another embodiment the direction change wheel includes a first wheel hub and a second wheel hub that are coupled together and jointly define an installation space. The magnetic element is located in the installation space and fixedly mounted onto the first wheel hub.

In yet another embodiment the first wheel hub has an installation trough to hold the magnetic element.

In yet another embodiment the second wheel hub has a confining rib corresponding to the magnetic element to collaborate with the installation trough to confine the magnetic element.

In yet another embodiment the magnetic element is located on the direction change wheel perpendicular to the magnetic induction unit.

In yet another embodiment the direction change wheel includes a wheel shaft interposed by the first wheel hub and the second wheel shaft, a wheel hood coupled with the wheel shaft and a transmission shaft coupled with the wheel hood and controlled by the drive module to generate direction turning.

In yet another embodiment the direction change wheel is located at the bottom of the front side of the body.

The invention, by means of the structure set forth above, compared with the conventional technique, can provide many advantageous features, notably:

1. With a magnetic element located on the direction change wheel, the magnetic induction unit located on the device body corresponding to the magnetic element can get induction from magnetism alteration of the magnetic element generated by driving of the direction change wheel while the self-moving sweeping device is moving, through the magnetism alteration of magnetic element whether the self-moving sweeping device has encountered an obstacle can be judged and a corresponding escape measure can be taken.

2. The invention mainly detects magnetism alteration of the magnetic element to determine movement condition of the direction change wheel, hence can avoid interference of external objects to prevent faulty judgment.

3. The structure of the invention is simpler in assembly.

The foregoing, as well as additional objects, features and advantages of the invention will be more readily apparent from the following detailed description, which proceeds with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an embodiment of the invention.

FIG. 2 is a block diagram of structural units of an embodiment of the invention.

FIG. 3 is an exploded view of the direction change wheel of an embodiment of the invention.

FIG. 4 is a fragmentary schematic view of an embodiment of the invention.

FIG. 5 is a fragmentary sectional view of an embodiment of the invention.

FIGS. 6 through 10 are schematic views of an embodiment of the invention in implementation conditions.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Please referring to FIGS. 1 and 5, the present invention aims to provide a self-moving sweeping device to perform dust suction operation on an area based on a preset behavior mode to achieve sweeping object. The self-moving sweeping device comprises a device body 10, at least two movement wheels 11 and a direction change wheel 12. The device body 10 includes a first shell segment 101 and a second shell segment 102 that are coupled together to jointly define a housing space 103. Furthermore, the device body 10 is equipped with a dust suction module 104, a drive module 105 and a behavior control module 106 connected to the dust suction module 104 and the drive module 105 in the housing space 103. The dust suction module 104 is driven by the behavior control module 106 to perform dust suction operation on a movement path of the self-moving sweeping device. The drive module 105 is controlled by the behavior control module 106 to generate corresponding actions. The drive module 105 can include an electric motor and a mechanical transmission structure. The behavior control module 106 can be preloaded with a plurality of duty modules to control works of the dust suction module 104 and the drive module 105. In addition, the behavior control module 106 can be preloaded with a movement mode with a swivel locus, a movement mode with a straight line locus and a movement move mode along a wall. Once the self-moving sweeping device is activated to perform work the behavior control module 106 judges the location of the self-moving sweeping device and determines to control the drive module 105 to do work through one of the aforesaid movement modes. For instance, when the behavior control module 106 judges that the self-moving sweeping device is located at an open site, the drive module 105 can be driven by the swivel movement mode or the straight line movement mode to perform dust suction operation according to a corresponding locus. In addition, the behavior control module 106 can be an electronic processing module.

Please also referring to FIGS. 1 and 2, the movement wheels 11 are located at the bottom of the device body 10 and connected to the drive module 105 to be driven thereof to generate rotation to drive the device body 10 to move. The direction change wheel 12 also is located at the bottom of the device body 10 same as the movement wheels 11 and also is controlled by the drive module 105 to guide direction turning of the device body 10. Moreover, the direction change wheel 12 can be located at the bottom of the front side of the device body 10 and includes a first wheel hub 121 and a second wheel hub 122 coupled together. The first wheel hub 121 and the second wheel hub 122 can be hollow and coupled to jointly form an installation space 123. In addition, the direction change wheel 12 can further include a wheel shaft 124 interposed between the first wheel hub 121 and the second wheel hub 122, a wheel hood 125 coupled with the wheel shaft 124 and a transmission shaft 126 coupled with the wheel hood 125 and controlled by the drive module 105 to generate direction turning. More specifically, the direction change wheel 12 is connected to the drive module 105 via the transmission shaft 126. When the drive module 105 is controlled by the behavior control module 106 to make the direction change wheel 12 to turn in direction and change the movement direction of the self-moving sweeping device, the drive module 105 orders the transmission shaft 126 to turn rightward or leftward for an angle, and consequently drives the wheel hood 125 to turn at the angle at the same time, thereby drives the first wheel hub 121 and the second wheel hub 122 to turn at the angle to make the self-moving sweeping device to generate direction turning.

In addition, the direction change wheel 12 has a magnetic element 13 located thereon in the installation space 123 that can be a pillar structure. In one embodiment, in order to facilitate installation of the magnetic element, the first wheel hub 121 has an installation trough 127 to hold the magnetic element 13, and the second wheel hub 122 has a confining rib 128 corresponding to the magnetic element 13 to collaborate with the installation trough 127 to confine the magnetic element. Thus the magnetic element 13 can be fixedly mounted onto the direction change wheel 12 to turn with the direction change wheel 12. Furthermore, the magnetic element 13 includes a first magnetic pole 131 and a second magnetic pole 132 that are repulsive against each other in magnetism. To facilitate discussion of the invention in actual implementation, it is presumed that the first magnetic pole 131 is N in magnetism, while the second magnetic pole 132 is S in magnetism, but this is not the limitation of the invention. On the other hand, the device body 10 also has a magnetic induction unit 107 faced the direction change wheel 12 that is designed to detect presence of the first magnetic pole 131 to generate a detection signal sent to the behavior control module 106. More specifically, the magnetic induction unit 107 is designed to generate reaction merely to a single magnetism, namely only to the N magnetism in this embodiment, then outputs a current to generate the detection signal. Thereby, because the magnetic element 13 is fixedly located on the direction change wheel 12, during the self-moving sweeping device is in movement turning of the direction change wheel 12 causes the magnetic induction unit 107 to generate synchronous movement to face the first magnetic pole 131 and the second magnetic pole 132 alternately, thereby the behavior control module 106 receives regularly the detection signal in a continuous and intermittent manner. In addition, to ensure that the magnetic element 13 can be detected by the magnetic induction unit 107 and present notable change of magnetism, the invention further has the magnetic element 13 mounted on the direction change wheel 12 perpendicular to the magnetic induction unit 107 as shown in FIG. 5.

During the self-moving sweeping device is in normal movement the behavior control module 106 receives the detection signal regularly in a continuous and intermittent manner. Hence the invention can judge whether the self-moving sweeping device moves abnormally based on whether the detection signal is received continuously within a monitor time. If positive, the self-moving sweeping device is judged moving normally; otherwise abnormally. More specifically, also referring to FIGS. 6 through 10, at the initial state after the self-moving sweeping device is activated, the behavior control module 106 drives the drive module 105 to make the movement wheels 11 to drive the device body 10 to move in one direction. In the event that the self-moving sweeping device does not encounter any obstacle during the movement the direction change wheel 12 rotates and the magnetic element 13 also is rotated to make the first magnetic pole 131 and the second magnetic pole 132 to face the magnetic induction unit 107 alternately so that the magnetic induction unit 107 generates regularly the detection signal in a continuous and intermittent manner, and the behavior control module 106 continuously receives the detection signal within the monitor time (such as five seconds or ten seconds), and judges that the self-moving sweeping device is moving normally. By contrast, during the movement of self-moving sweeping device in the event that the direction change wheel 12 is suspended due to an obstacle 2 and cannot turn in the movement of the self-moving sweeping device, the magnetic induction unit 107 cannot detect the regular change of the first magnetic pole 131 and the second magnetic pole 132, such as detecting the first magnetic pole 131 for a prolonged period of time, or does not detect the first magnetic pole 131 while the monitor time is over; as the behavior control module 106 cannot continuously receive the detection signal within the monitor time, it judges that the self-moving sweeping device is moving abnormally and enters an escape state.

Please referring to FIGS. 7 through 10, when the self-moving sweeping device enters the escape state the behavior control module 106 reads a preloaded escape mode, for instance, controls the drive module 105 to make the movement wheels 11 to rotate in reverse and move away from the obstacle 2 as shown in FIG. 8. Thereafter, referring to FIGS. 9 and 10, the behavior control module 106 can further control the drive module 105 to drive the direction change wheel 12 to turn and move away from the obstacle 2 and guide the self-moving sweeping device to continuously perform the dust suction operation.

In yet another embodiment the behavior control module 106 can also capture the appearing frequency of the detection signal within the monitor time and convert it to a frequency signal, and further judge whether the self-moving sweeping device is moving abnormally based on the frequency signal. In the event that alterations take place on the frequency signal and decreases gradually the self-moving sweeping device is judged in an abnormal movement condition. As an example for furthermore discussion, presumed that during the self-moving sweeping device is in normal movement the behavior control module 106 captures the generated frequency signal ten times per second; when the self-moving sweeping device encounters the obstacle 2 during the dust suction operation that reduces the rotation speed of the direction change wheel 12, the behavior control module 106 captures the frequency signal that gradually decreases from the original ten times per second, it judges that the self-moving sweeping device has encountered an obstacle and moved abnormally.

The obstacle mentioned above is not limited to ordinary objects, can also be ropes or hairs entangled the direction change wheel 12, or even notable uneven floor surface.

As a conclusion, the self-moving sweeping device of the invention includes a device body and at least two movement wheels and a direction change wheel located at the bottom of the device body. The direction change wheel includes a magnetic element turnable therewith that includes a first magnetic pole and a second magnetic pole repulsive against each other in magnetism. The device body has a magnetic induction unit faced the direction change wheel. During movement of the device body the magnetic induction unit detects in normal conditions whether the first magnetic pole generates a detection signal sent to the behavior control module which determines whether the self-moving sweeping device is moving abnormally based on whether the detection signal is received continuously within a monitor time; if positive, the self-moving sweeping device is judged in normal movement; otherwise, abnormal movement. Thus the probability of faulty movement of the self-moving sweeping device can be reduced, and an escape measure can be taken at the initial state of the faulty movement to enhance the work stability of the self-moving sweeping device. 

What is claimed is:
 1. A self-moving sweeping device, comprising: a device body equipped with a dust suction module, a drive module and a behavior control module connected to the dust suction module and the drive module, the behavior control module determining work of the dust suction module and the drive module; at least two movement wheels located at the bottom of the device body and connected to the drive module and driven by the drive module to generate rotation to drive the device body to move; and a direction change wheel located at the bottom of the device body with the movement wheels and controlled by the drive module to guide direction change of the device body in movement; wherein the direction change wheel includes a magnetic element which is turnable with the direction change wheel and includes a first magnetic pole and a second magnetic pole repulsive against each other in magnetism, the device body including a magnetic induction unit faced the direction change wheel to detect whether the first magnetic pole has generated a detection signal sent to the behavior control module during movement of the device body, the behavior control module determining whether the self-moving sweeping device moves abnormally based on whether the detection signal has been continuously received within a monitor time; the self-moving sweeping device being judged in normal movement when the detection signal has been received continuously within the monitor time; otherwise, judged abnormal.
 2. The self-moving sweeping device of claim 1, wherein the behavior control module captures the appearing frequency of the detection signal within the monitor time and converts to a frequency signal and judges whether the self-moving sweeping device in abnormal movement based on the frequency signal; and judges the self-moving sweeping device in abnormal movement when the frequency signal changes and decreases gradually.
 3. The self-moving sweeping device of claim 1, wherein the direction change wheel includes a first wheel hub and a second wheel hub that are coupled together and jointly define an installation space, the magnetic element being located in the installation space and fixedly mounted onto the first wheel hub.
 4. The self-moving sweeping device of claim 3, wherein the first wheel hub includes an installation trough to hold the magnetic element.
 5. The self-moving sweeping device of claim 4, wherein the second wheel hub includes a confining rib corresponding to the magnetic element and collaborating with the installation trough to confine the magnetic element.
 6. The self-moving sweeping device of claim 4, wherein the magnetic element is located on the direction change wheel perpendicular to the magnetic induction unit.
 7. The self-moving sweeping device of claim 3, wherein the direction change wheel includes a wheel shaft interposed between the first wheel hub and the second wheel hub, a wheel hood coupled with the wheel shaft and a transmission shaft coupled with the wheel hood and controlled by the drive module to generate direction turning.
 8. The self-moving sweeping device of claim 1, wherein the direction change wheel is located at the bottom of a front side of the device body. 